synthetic oil?

I was wondering what you guys thought about using synthetic oil. Someone told me the 5w40 full synthetic diesel oil is great. What arw your thoughts? Do they make a heavier synthetic for diesels? The heaviest I can find is the 5w40. Will this be fine in my 7.3 or should I use conventional?

Follow up. I currently have a synthetic blend In and just got to 4000 miles. So I went and bought a new oil filter and changed it and topped it off with rotella 5w40 full synthetic. After this I noticed a considerable gain in power. Is this because of the thinner oil and the hpop can pump easier making the injectors more efficient?

Hi Glenn, so you tow about 15k in about 6 months. How many times do you change oil and filter during that 15k? How bout other fluids and regular maintenance you find necessary, and what are some of the of the surprises you have had on those long trips?
You are truly a testimonial and supporter of Shaeffers, you should get at least a gold starr for your support. I hope your trip is going well this year

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